I have a fuel leak where the fuel heater comes through the top of the filter housing on my daily driver 1991 f250, it is the o-ring that is leaking so I went to ford to get a new one only to find that it has been discontinued and none of the dealers in the entire state had any leftover stock. The guy behind the counter was trying his best to help but couldnt even find what size the o-ring was.
Do any of you guys know what size the o-ring is and/or where i can get one to replace it as I really dont want to spend $130 on an entire fuel heater assembly I dont need. The guy at ford told me not to use a standard black o-ring because it wasnt made of the right material and that I needed to use a blue or green one made of viton. the bad thing is i just bought a fuel heater for my f350 and it came with an extra o-ring that was blue and now i cant find it...AARRRGH!
Thanks for any light you guys can shed on this one

 

I'm sure someone here can get you the size info. I think Viton O-rings are the ones you want. That's what I use on my injector caps and You can get a pack of 50 for pretty cheap. They stand up to fuel and heat really good

 

IIRC they are 5/8"ID 3/4"OD and you should be able to get them at a local parts store.

Yes, Viton is better, Buna-N will live along time in that location.

Lube them up with Petrolatum. (Vaseline)

-Enjoy
fh : )_~

 

Same as the injector o-ring.

 

A return o-ring works in a pinch, but the cross section is thicker and is to tight ... 3/32 versus 1/16.

-Enjoy
fh : )_~

 

I got new heater O-rings from my local IH service center. They even had the rubber seal for the drain on the two piece fuel filter.

 

i just eliminated the heater. threaded a bolt in the hole and JB-Weld it sealed.been that way for around 25 years and never missed having the heater, even at 10 below.

 

Tap for 1/2-npt and stick a plug in it. I did that on my van when it decided to start gushing.

 

+1 on the pipe plug. I put some loctite on mine to seal the threads. The heater is not needed.

 

So I tried the o-ring and it worked, unfortunately I quickly realized that the o-ring had not been the problem, the fuel was coming from around the metal electrical terminal and with the plug off was actually making a little geyser of diesel fuel. I didnt have a 1/2 inch pipe plug tap with me so I just robbed the entire filter housing off my 86 since it had the 7.3 style housing on it and i will take the other housing to work and tap and plug it since the 86 has an inline heater it is not necessary to have one in the filter housing. Would I be best to use a brass, steel or iron plug? I have all 3 at work. Thanks

 

i would use brass, because it will never rust or rot.
but you can use whatever you have laying around. i used a stainless bolt because that is the first thing i grabbed.

 

If the heater works, put o-rings in it, if the heater is broke, tap it for 1/2" NPT and put a brass countersunk plug in it ...

That's what I would do!

-Enjoy
fh : )_~